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Date: Sun, 25 Jan 2015 14:24:07 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Jiri Olsa <jolsa@redhat.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Namhyung Kim <namhyung@kernel.org>
Subject: Re: [PATCH 2/5] tools lib api fs: Add tracefs mount helper
 functions
Message-ID: <20150125142407.3759c577@gandalf.local.home>
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References: <20150124181330.195149364@goodmis.org>
	<20150124181448.680347393@goodmis.org>
	<20150125165114.GE31987@krava.brq.redhat.com>
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On Sun, 25 Jan 2015 17:51:14 +0100
Jiri Olsa <jolsa@redhat.com> wrote:

> On Sat, Jan 24, 2015 at 01:13:32PM -0500, Steven Rostedt wrote:
> 
> SNIP
> 
> > +static const char * const tracefs_known_mountpoints[] = {
> > +	TRACEFS_DEFAULT_PATH,
> > +	"/sys/kernel/debug/tracing",
> > +	"/tracing",
> > +	"/trace",
> > +	0,
> > +};
> > +
> > +static bool tracefs_found;
> > +
> > +/* find the path to the mounted tracefs */
> > +const char *tracefs_find_mountpoint(void)
> > +{
> > +	if (tracefs_found)
> > +		return (const char *)tracefs_mountpoint;
> > +
> > +	return find_mountpoint("tracefs", (long) TRACEFS_MAGIC,
> > +			       tracefs_mountpoint, PATH_MAX + 1,
> > +			       tracefs_known_mountpoints);
> > +}
> 
> also tracefs_found is not set 'true' in case we succeed..
> 

Thanks will fix. This is something that testing wouldn't catch, because
the tracefs_found (and debugfs_found) are just there to not try to
remount. Where here it would just refind where it is mounted. Thus, not
incorrect code, just inefficient code.

-- Steve